Olefin-based thermoplastic elastomer compositions have been used widely for automotive interior parts, automotive exterior parts, electrical machinery parts, household appliance parts, packaging members, agricultural materials, building members, etc. because they are capable of being processed with a common molding machine for thermoplastic resins and being recycled and they are soft (see patent document 1). However, since thermoplastic elastomers are flammable materials, they must be made flame retardant for some applications.
Well known methods for making a synthetic resin flame retardant include methods in which an inorganic phosphorus-based flame retardant such as red phosphorus and phosphorus-containing flame retardants, an organophosphorus flame retardant such as triaryl phosphate compounds, a halogen-containing flame retardant, or a metal hydroxide flame retardant is added, and, optionally, a flame retarding aid such as antimony oxide, a melamine compound is further added into a synthetic resin. (See patent documents 2 to 4.)